Apparatus for cleaning loose filtering material in slow water filled water supply filters

ABSTRACT

An apparatus for cleaning loose filtering material in slow water-filled water supply filters, comprising a washing chamber equipped with means for its movement relative to the surface of the loose filtering material being cleaned. Mounted inside the washing chamber are washing tubes to feed clean water into the layer of filtering material to be washed. The washing chamber communicates with a suction pipe which evacuates dirty water therefrom. The chamber is provided with means for regulating its pressure upon the filtering material by controlling its degree of buoyancy.

[451 May 15, 1973 United States Patent [1 1 Volokh [54] APPARATUS FORCLEANING LOOSE Primary Examiner-Samih N. Zaharna FILTERING MATERIAL INSLOW A ttorney-Waters, Roditi, Schwartz & Nissen WATER FILLED WATERSUPPLY FILTERS ABSTRACT m. 343 .nR new /3 02 fld I M, 0 0 B IS u an vhW" O M4 mm m m 7 m m m m 4 m Fara 7 mm 2 0 .mm m r 8 OM 5 BPM] n "e r 0MS m LM n L C e e D. .l V D. m vm FA UIF 1 1]] 6 2 218 7 22 555 .l [.l

References Cited 2 Claims, 2 Drawing Figures UNITED STATES PATENTSSivade.................

APPARATUS FOR CLEANING LOOSE FILTERING MATERIAL IN SLOW WATER FILLEDWATER SUPPLY FILTERS The invention relates to equipment for cleaningloose filtering materials, and particularly to apparatus used to cleanthe loose filtering material in slow-operating water supply filters.

Known in the art is an apparatus to clean loose filtering materials inslow water-filled water supply filters, which comprises a washingchamber. The chamber is open from below, its open side adjoining in thecourse of work the layer section of the filtering loose material beingcleaned. Two opposite side walls of the chamber have bottom portionsthat are bent aside from the chamber, and slide against the layer of thefiltering ma terial being treated as the chamber moves therealong. Theother two opposite side walls have edges extending downward below saidbent off portions, which edges cut into the filtering layer during thechamber movement. The bent off portions of two side walls and theextending edges of the other two side walls bound in plan the section ofthe filtering material which is being cleaned.

Disposed inside the chamber are washing tubes serving to feed washingwater into the filtering layer being cleaned, the tubes being submergedinto the filtering material to a specified depth during the operation ofthe apparatus.

The washing tubes are connected to a continuous header communicating thewashing chamber to the environment through the washing tubes. Alsoavailable in the chamber is a suction pipe for evacuating dirty water.The chamber is secured to a cable which is connected to a winch mountedbeyond the filter, and serving to movethe chamber along the surface ofthe filtering layer.

When the apparatus is in operation, the chamber is sunk into the filterunder the water layer, and placed onto the filtering material. As thepump which evacuates water from the wash chamber is set into action, theextending edges of the side walls and the washing tubes fully submergeinto the filtering layer, the chamber thus tightly seating on itssurface. Vacuum is generated in the wash chamber, and the starting watercontained in the filter enters the header under atmospheric pressure,and then the washing tubes, thereupon passing into the layer offiltering material. The layer of filtering material is stirred, the dirtbeing carried away to the suction pipe wherefrom it is pumped out alonga hose to the sewerage. In the process of cleaning, the chamber is movedalong the layer of filtering material. The washing tubes are in thesuspended layer of the filtering material, thus not encountering anylarge resistance in the course of the chamber movement.

After the washing chamber has been pulled all across the length of thefilter, having cleaned a strip of the filtering layer of a widthequaling that of the washing chamber, the latter is displaced to theadjacent strip, the cleaning cycle being resumed.

However, the prior art apparatus has the disadvantage, that it does notpermit regulating the force of the chamber pressure on the layer of thefiltering material being cleaned according to the depth of submersion ofthe washing tubes, and the depth of the water layer in the filter, whichinvolves the need to use unduly large forces for moving the chamberagainst the layer of filtering material. Large forces to move thechamber are also required due to the fact that evacuation of dirty waterfrom the chamber induces suction of the latter to the filtering layer.Moreover, shifting the chamber from one strip to another requireshoisting mechanisms, such as a crane.

An object of the invention is to provide an apparatus for cleaning slowwater supply filters, that allows rapid and simple adjustment of anoptimum chamber pressure on the layer of filtering material irrespectiveof the suction pump operation, the depth of submersion of the washingtubes, or the depth of the layer of the starting water in the filter,which makes possible realizing uninterrupted movement of the washingchamber with a minimum pulling force during its operation. Additionally,said apparatus requires no additional hoisting equipment for shiftingthe chamber from one strip of the filtering material being cleaned, toanother.

With said object in view, in an apparatus for cleaning loose filteringmaterial in slow water-filled water supply filters, comprising a washingchamber equipped with means for its movement relative to the surface ofthe loose filtering material being cleaned, washing tubes fitted insidethe chamber to feed clean water into the layer of loose filteringmaterial to be washed through, and a suction pipe to evacuate dirtywater from the washing chamber, the apparatus, according to theinvention, is provided with means for regulating its pressure upon thelayer of filtering material, and its degree of buoyancy.

The means for regulating the pressure of the washing chamber upon thelayer of filtering material, and its degree of buoyancy, are preferablymade in the form of at least one container incorporating facilities forits filling with a regulated amount of a gas medium.

The washing chamber may communicate with the atmosphere.

The invention is further exemplified with the description of particularembodiments thereof with reference to the appended drawings, wherein:

FIG. 1 is a schematic illustration in longitudinal sectional view of theapparatus for cleaning loose filtering material in slow water supplyfilters according to the invention, and

FIG. 2 is section taken on line Il1--II in FIG. 1.

The apparatus for cleaning loose filtering materials in slowwater-filled water supply filters comprises a washing chamber 1 (FIG.1), the open bottom of which adjoins the layer of filtering material 2being cleaned, of the slow water supply filter. Mounted on the housingof the washing chamber 1 are pumps 3 and 4.

Pump 3 is connected through a distributing header 5 to washing tubes 6,and serves to deliver wash water into the layer of the filteringmaterial 2 being cleaned, while pump 4 through a suction pipe 7communicates with drain pipes 8, and serves to draw away dirty water.

The length of pipes of the distributing header 5 equals the width of thewashing chamber 1, as is shown in FIG. 2, their number depending on thedesired efficiency of the apparatus.

In the pipes connecting pumps 3 and 4 (FIG. 1) with the distributingheader 5 and the drain pipes 8, respectively, throttles 9 are placed.

Both the distributing header 5 with washing tubes 6, and the drain pipes8 can be vertically displaced and fixed at any required depth, e.g. byscrews (not shown).

The washing chamber 1 communicates with the atmosphere, which rules outthe possibility of a vacuum being created therein in the process ofexhausting wash water with dirt, thus precluding any suction effect ofthe washing chamber 1 against the layer of the filtering material 2being cleaned, and reducing the pulling force required to move thewashing chamber 1.

Communication of the washing chamber 1 with the atmosphere also excludesaccumulation of the air released in washing through the filteringmaterial, inside the washing chamber 1, thereby providing normalconditions for the operation of pump 4 sucking off dirty water.

The washing chamber 1 is supplied with two containers serving toregulate its pressure on the filtering material by varying its degree ofbuoyancy. Containers 10 are connected to a source 11 of a compressedgas, which for example, may be an air compressor. The compressed gassource 11 should have a capacity to develop a pressure sufficient toexpel water from containers 10 when the water layer in the water supplyfilter to be cleaned has its maximum depth. Water enters containers 10and leaves them through openings 12.

Secured to the walls of the washing chamber 1 is a cable 13 of a pullingwinch (not shown), which can be mounted both on the housing of thewashing chamber 1, or beyond the slow water supply filter.

The possible direction of movement of the washing chamber 1 with respectto the layer of filtering material is shown by arrows in FIG. 2.

The side walls 14 of the washing chamber 1 are made to extend downwardsbelow the bottoms 15 (FIG. 1) of containers 10, so that during themovement of the washing chamber 1 their extending edges cut into thelayer of the filtering material 2. Bottoms 15 of containers 10 and theextending edges of the side walls 14 limit in plan the section of thefiltering material 2 being cleaned. The plan dimensions of the washingchamber 1 are chosen according to the required efficiency of theapparatus. The height of the washing chamber 1 should advantageously bemore, than the maximum thickness of the layer of water 16 contained inthe slow water supply filter during its cleaning.

The apparatus for the cleaning of loose filtering material in slowwater-filled water supply filters operates as follows.

The washing chamber 1 is sunk into the water-filled water supply filterwhose filtering material is to be cleaned.

Pump 4 evacuates water from the washing chamber 1 and discharges it tothe sewerage. Set into action together with pump 4 is pump 3 which takesthe starting water contained in the water supply filter, and feeds it tothe distributing header 5 and therefrom into the washing tubes 6. Thewater issuing from the washing tubes 6 washes away the loose filteringmaterial 2, thus providing for free and rapid submersion of the washingtubes 6 and the extending edges of walls 14 into the layer of filteringmaterial 2.

Within the area confined by the washing chamber the layer of filteringmaterial 2 is stirred up to the depth of submersion of the washing tubes6, resulting in the formation ofa suspended layer of filtering materialwhich lifts to the washing chamber 1.

Air released while washing through the filtering material 2, havingpassed through the layer of water in the washing chamber 1, escapes tothe atmosphere.

Due to the continuous suction of water from the washing chamber 1, thereis formed therein a steady water flow directed toward the drain pipes 8.This flow draws into the drain pipes 8 the dirt washed off as a resultof stirring the filtering material 2, which dirt is then exhausted bypump 4.

The washing chamber 1 is pulled across the entire length of the watersupply filter, the washing tubes 6 being all this time located withinthe suspended layer of the filtering material 2, and thus meeting nosubstantial resistance during the movement of the washing chamber 1.

In the course of movement of the washing chamber 1 the pressurized washwater is fed to the forward pipe of the distributing header 5, withrespect to the direction of movement of the washing chamber 1, while thedirty water is pumped out through the rear drain pipe 8, for whichpurpose the appropriate throttles 9 are closed or opened. This reducesthe required pulling force on cable 13, the discharge of wash water, andthe amount of fine sand carried away to the sewerage.

After the washing chamber 1 has been pulled all across the length of thewater supply filter, having cleaned a strip of the layer of filteringmaterial 2 with a width equaling that of the washing chamber 1, thelatter is imparted with positive buoyancy. The washing chamber 1completely floats in the water, and by applying an insignificant forceit is shifted to the adjacent strip, where the cleaning cycle isresumed.

The imparting of positive buoyancy to the washing chamber 1, as well asthe adjusting of its pressure upon the layer of filtering material 2 iseffected by filling containers 10 with a required amount of gas medium,which is regulated according to the depth of submersion of the washingtubes 6 into the layer of filtering material 2, and the depth of thewater layer in the water supply filter.

THe proposed apparatus ensures a high degree of washing of the filteringmaterial, is simple in operation, and features low power consumption.

The described apparatus can as well be employed for cleaning filteringmaterial in water-filled infiltration basins.

What I claim is:

1. An apparatus for cleaning loose filtering material in slowwater-filled water supply filters, comprising: a washing chamber havingan open bottom and submersible in the water of the filter to rest on thesurface of a layer of filtering material to be cleaned; means for movingsaid washing chamber on the surface of the layer of filtering material;washing tubes mounted in said chamber to feed clean water into saidlayer of filtering material to be washed; a suction pipe in said chamberto evacuate dirty water from said washing chamber; and means forregulating the degree of buoyancy of the washing chamber in the water ofthe filter to regulate the pressure of said washing chamber upon thelayer of filtering material, said means for regulating the degree ofbuoyancy of said washing chamber comprising at least one closedcontainer associated with said chamber, said container having a lowerport through which water in the filter can enter and leave the containerand means for filling said container with a controlled amount of gas.

2. Apparatus as claimed in claim 1 wherein said washing chamber has anopen top to communicate with the atmosphere.

1. An apparatus for cleaning loose filtering material in slowwater-filled water supply filters, comprising: a washing chamber havingan open bottom and submersible in the water of the filter to rest on thesurface of a layer of filtering material to be cleaned; means for movingsaid washing chamber on the surface of the layer of filtering material;washing tubes mounted in said chamber to feed clean water into saidlayer of filtering material to be washed; a suction pipe in said chamberto evacuate dirty water from said washing chamber; and means forregulating the degree of buoyancy of the washing chamber in the water ofthe filter to regulate the pressure of said washing chamber upon thelayer of filtering material, said means for regulating the degree ofbuoyancy of said washing chamber comprising at least one closedcontainer associated with said chamber, said container having a lowerport through which water in the filter can enter and leave the containerand means for filling said container with a controlled amount of gas. 2.Apparatus as claimed in claim 1 wherein said washing chamber has an opentop to communicate with the atmosphere.